Hydroxy-phenoxyether polymers in papermaking

ABSTRACT

Paper comprised of suitable amounts of a hydroxy-phenoxyether polymer is effective to provide that paper with an increase in sizing or strength. Such paper may be prepared by intermixing dispersions or solutions of hydroxy-phenoxyether polymer with the pulp slurry or web during papermaking, or by application to formed paper. Paper may be coated or laminated by applying such dispersions or solutions.

RELATED APPLICATION INFORMATION

[0001] This application claims priority under 35 U.S.C. §119(e) to thefollowing U.S. provisional applications: Serial No. 60/172,714, filedDec. 20, 1999, Serial No. 60/194,959, filed Apr. 5, 2000, Serial No.60/212,919, filed Jun. 20, 2000, and Serial No. 60/228,188 filed Aug.25, 2000, the disclosures of which are hereby incorporated by referencein their entireties.

BACKGROUND OF INVENTION

[0002] 1. Field of the Invention

[0003] This invention relates to paper and methods for making paper thatinvolve the use of hydroxy-phenoxyether polymers to provide the paperwith improved properties such as increased sizing and strength. Thisinvention also relates to coated paper and laminates comprised of paperand hydroxy-phenoxyether polymers, and to methods for making them. Inpreferred embodiments, the paper and laminates are recyclable.

[0004] 2. Description of the Related Art

[0005] Paper is a highly versatile material that is used throughout theworld for a variety of applications. The properties of paper tend to bedominated by the properties of the cellulosic materials from which it ismade, unless additives are used to modify, control or enhance theseproperties. To some extent, the versatility of paper results from thedegree to which the basic properties of cellulosic materials may becontrolled by the use of papermaking additives. To this end, a widevariety of such additives are known to those skilled in the art.

[0006] For instance, the degree to which paper resists penetration bywater and other liquids may be controlled through the use of sizingagents. Sizing agents may be applied to the surface of the paper toachieve surface sizing, or may be incorporated into the bulk of thepaper by intermixing the sizing agent with the aqueous cellulosic pulpslurry during processing. Because cellulosic materials tend to berelatively hydrophilic, paper usually has relatively poor sizing in theabsence of sizing agents. Typical sizing agents are relativelyhydrophobic substances that are emulsified or dispersed into water, thenintermixed with the pulp slurry, paper web or formed paper by a varietyof known techniques to render the paper more hydrophobic and thusincrease its resistance to permeation by liquids such as water. Alkenylsuccinic anhydride (ASA) and alkyl ketene dimer (AKD) are widely used tosize paper in commercial practice, but they are reactive substances thatare generally put into the form of a suitable emulsion by a complicatedon-site mixing process. Thus, there is a need for sizing agents that areeasier to use and which exhibit commercially acceptable sizingperformance.

[0007] In a number of cases paper has relatively poor dry strength inthe absence of additives. In many applications, such as packaging, gooddry strength is often desirable. Water-soluble polymers such aspolyacrylamide are widely used in commercial practice to provideincreased dry strength. These polymers may be conveniently incorporatedinto paper by dissolving them in the aqueous processing medium, e.g.,the pulp slurry. However, for many applications these polymers do notprovide adequate wet strength because of their tendency to dissolve inwater. Good wet strength is often desirable in many packagingapplications. Thus, there is a need for polymer additives which providesuitable dry strength but which also provide acceptable wet strength.

[0008] Many of the polymer additives used commercially to provide wetstrength are capable of forming bonds to the cellulosic material or arecapable of forming a crosslinked or network structure that does notfully dissolve, thus providing so-called “permanent” wet strength.Examples of permanent wet strength resins typically used in commercialpractice are polyamine epichlorohydrin, polyamide epichlorohydrin andpolyamine-amide epichlorohydrin. But in some cases permanent wetstrength is undesirable because the crosslinked nature of the resinrenders the resulting paper more difficult to recycle. So-called“temporary” wet strength resins tend to be easier to recycle becausethey have a degree of wet strength that decays over time upon exposureto water. An example of a temporary wet strength resin is glyoxalatedvinylamide. However, these resins may be unsuitable for applications inwhich permanent wet strength is desirable. Thus, there is a need forpermanent wet strength resins which are compatible with recycling.

[0009] In the absence of additives, paper is generally a rather flexiblematerial and thus has relatively poor stiffness or flexural strength,especially when wet or when exposed to cyclic humidity. The industrycurrently coats the paper with wax to make it more stiff. However, waxmakes the paper much more difficult to recycle. The presence of waxtends to weaken the recycled paper and to reduce its coefficient offriction, leading to problems in converting and handling. Thus, there isa need for an additive and/or coating for paper that is capable ofproviding enhanced flexural strength, especially under wet conditions,and that is compatible with recycling.

[0010] The use of any particular additive may also be complicated byrequirements imposed by the process. For instance, ASA-type sizingagents are generally considered to be compatible with alkaline sizingprocesses, whereas many other sizing agents are not. Also, secondaryadditives are frequently used to increase the performance of theadditive having the primary effect; e.g., emulsifiers are often added tothe sizing agent to facilitate production of the sizing emulsions. Inaddition, the industry generally prefers more environmentally compatibleprocesses, e.g., to decrease the level of pollutants produced during thepapermaking process and to increase the degree to which the resultingpaper can be recycled. Finally, the demands of the consumer frequentlychange, e.g., in recent years the demand for paper compatible withink-jet printers has generally risen as those printers have become morewidely available. Thus, there is a need for polymer additives which aregenerally compatible with existing processes and equipment and which areversatile enough to enable future compliance with the demands imposed bysociety and the consumer.

[0011] Hydroxy-phenoxyether polymers are known, see e.g. U.S. Pat. Nos.6,011,111; 5,834,078; 5,814,373; 5,464,924; and 5,275,853; see also PCTApplication Nos. WO 99/48962; WO 99/12995; WO 98/29491; and WO 98/14498.However, these disclosures do not address the aforementioned problems.

SUMMARY OF THE INVENTION

[0012] The inventors have discovered that hydroxy-phenoxyether polymersmay be used to provide the paper with various desirable properties, suchas increased sizing and/or strength. This benefits the papermaker byproviding a new category of polymers suitable for use in papermaking.The papermaker may use these polymers as an alternative to, or inconjunction with, existing papermaking additives. Manufacturers ofpaper-containing goods also benefit by gaining access to a new type ofpaper for incorporation into various manufactured articles. The consumerwho purchases these products benefits when the paper provides improvedproperties that increase the consumer's enjoyment of the product, orwhen the paper provides suitable properties at an acceptable cost.Finally, all of humanity benefits when the manufacture of the paper ismore efficient and less polluting, and when the paper-containing productis recyclable.

[0013] Preferred embodiments provide paper comprised of an amount ofhydroxy-phenoxyether polymer that is effective to provide the paper withan increase in sizing or strength. In a more preferred embodiment, thehydroxy-phenoxyether polymer is a polyetheramine. In another morepreferred embodiment, the increase in strength is an increase in wettensile strength, dry tensile strength, wet flexural strength or dryflexural strength. In yet another more preferred embodiment, theincrease in sizing is an increase in Cobb sizing, as manifested by adecrease in Cobb value. In yet another preferred embodiment, the paperis readily recyclable.

[0014] In another preferred embodiment, a process for making paper isprovided, comprising providing a pulp slurry or paper web, providing asolution or dispersion comprised of a hydroxy-phenoxyether polymer,intermixing the solution or dispersion with the pulp slurry or paper webto form an admixture, and forming paper from the admixture, wherein thehydroxy-phenoxyether polymer is used in an amount that is effective toprovide the paper with an increase in sizing or strength. In a morepreferred embodiment, the pH of the admixture is adjusted, toprecipitate a least a portion of the hydroxy-phenoxyether polymer and/orto be in the range of about 4 to about 7.

[0015] In still another preferred embodiment, a process for coatingpaper is provided, comprising providing a paper, providing a solution ordispersion comprised of a hydroxy-phenoxyether polymer, applying thesolution or dispersion to at least a portion of the paper to form a wetpaper, and drying the wet paper to form a coated paper. In a morepreferred embodiment, this process further comprises forming a wetlaminate by bringing the wet paper or the coated paper into contact witha solid material, a second solution or dispersion comprised of ahydroxy-phenoxyether polymer, or a mixture thereof, and drying the wetlaminate to form a laminate.

[0016] In still another preferred embodiment, a laminate is provided,comprised of hydroxy-phenoxyether polymer, at least one layer comprisedof paper, and at least one layer comprised of a second paper or a solidnon-paper material.

[0017] In yet another preferred embodiment, a method of obtainingrecycled hydroxy-phenoxyether polymers from paper comprisinghydroxy-phenoxyether polymers is provided, comprising: providing a papercomprising a hydroxy-phenoxyether polymer; contacting the paper with anaqueous solution comprising 1-50% acid by weight to at least partiallydissolve the hydroxy-phenoxyether polymer to form an acidichydroxy-phenoxyether polymer solution; separating the acidichydroxy-phenoxyether polymer solution from any solids present; adding abase to the acidic hydroxy-phenoxyether polymer solution to form ahydroxy-phenoxyether polymer precipitate; and separating thehydroxy-phenoxyether polymer precipitate.

[0018] These and other embodiments are described in greater detailbelow.

BRIEF DESCRIPTION OF THE DRAWINGS

[0019]FIG. 1 is a bar graph of the compressive strength of molded papersamples as a function of sample thickness and amount ofhydroxy-phenoxyether polymer contained within the paper.

[0020]FIG. 2 is a plot of the load vs. number of cycles for 3 moldedpaper samples containing various amounts of hydroxy-phenoxyetherpolymer.

[0021]FIG. 3 shows a non-limiting example of a flow diagram thatillustrates various aspects of a typical papermaking process.

[0022]FIG. 4 shows a non-limiting schematic diagram that illustratesvarious aspects of a “puddle” size press.

[0023]FIG. 5 shows a non-limiting schematic diagram that illustratesvarious aspects of a metering size press.

[0024]FIG. 6 shows non-limiting schematic diagrams that illustratevarious types of roll coaters.

[0025]FIG. 7 shows non-limiting schematic diagrams that illustratevarious aspects of blade and air knife coaters.

[0026]FIG. 8 shows a non-limiting schematic diagram that illustratesvarious aspects of a simple short dwell coater.

[0027]FIG. 9 is a flow diagram for a preferred paper recycling process.

[0028]FIG. 10 is a flow diagram for a preferred paper recycling process.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0029] The preferred embodiments relate to paper comprised of ahydroxy-phenoxyether polymer and methods of making such paper. The term“paper,” as used herein, is a broad term and is used in its ordinarysense to include, without limitation, all manner of processed or moldedcellulosic materials and thus includes all types of paper productsproduced from a cellulosic pulp slurry, including without limitationintermediate paper fiber products, finished products such as thin sheetsof paper used for documents, books, newspapers, magazines and the likeand heavier grades of paper such as cardboard, multi-ply paper, paperlaminates, coated paper, corrugated paper, molded paper, and paper usedfor packaging, shipping containers and the like, without limitation. Theterm “pulp slurry,” as used herein, is a broad term and is used in itsordinary sense to include, without limitation, an aqueous slurrycontaining cellulose or cellulosic fiber derived from a plant or woodpulping process or paper recycling process, regardless of whether suchcellulose is derived from plants such as cotton or from hardwood orsoftwood or combinations thereof, and regardless of whether the pulpingprocess(es) employed to provide such slurry is categorized as amechanical or chemical or secondary or hybrid pulping process, orwhether the slurry is derived from a plurality of types of pulpingprocesses, and regardless of whether or not the pulp, or part of thepulp, has been bleached.

[0030] The term “hydroxy-phenoxyether polymer,” as used herein, is abroad term and is used in its ordinary sense to include, withoutlimitation, a polymer having aromatic ether moieties in its backbonechain and pendant hydroxyl groups, see e.g. U.S. Pat. No. 6,011,111(incorporated herein by reference in its entirety). Preferredhydroxy-phenoxyether polymers are as follows:

[0031] (1) hydroxy-functional poly(amide ethers) having repeating unitsrepresented by any one of the Formulae Ia, Ib or Ic:

[0032] (2) poly(hydroxy amide ethers) having repeating units representedindependently by any one of the Formulae IIa, IIb or IIc:

[0033] (3) amide- and hydroxymethyl-functionalized polyethers havingrepeating units represented by Formula III:

[0034] (4) hydroxy-functional polyethers having repeating unitsrepresented by Formula IV:

[0035] (5) hydroxy-functional poly(ether sulfonamides) having repeatingunits represented by Formulae Va or Vb:

[0036] (6) poly(hydroxy ester ethers) having repeating units representedby Formula VI:

[0037] (7) hydroxy-phenoxyether polymers having repeating unitsrepresented by Formula VII:

[0038] and

[0039] (8) poly(hydroxyamino ethers) having repeating units representedby Formula VIII:

[0040] wherein each Ar individually represents a divalent aromaticmoiety, substituted divalent aromatic moiety or heteroaromatic moiety,or a combination of different divalent aromatic moieties, substitutedaromatic moieties or heteroaromatic moieties; R is individually hydrogenor a monovalent hydrocarbyl moiety; each Ar₁ is a divalent aromaticmoiety or combination of divalent aromatic moieties bearing amide orhydroxymethyl groups; each Ar₂ is the same or different than Ar and isindividually a divalent aromatic moiety, substituted aromatic moiety orheteroaromatic moiety or a combination of different divalent aromaticmoieties, substituted aromatic moieties or heteroaromatic moieties; R₁is individually a predominantly hydrocarbylene moiety, such as adivalent aromatic moiety, substituted divalent aromatic moiety, divalentheteroaromatic moiety, divalent alkylene moiety, divalent substitutedalkylene moiety or divalent heteroalkylene moiety or a combination ofsuch moieties; R₂ is individually a monovalent hydrocarbyl moiety; A isan amine moiety or a combination of different amine moieties; X is anamine, an arylenedioxy, an arylenedisulfonamido or an arylenedicarboxymoiety or combination of such moieties; and Ar₃ is a “cardo” moietyrepresented by any one of the Formulae:

[0041] wherein Y is nil, a covalent bond, or a linking group, whereinsuitable linking groups include, for example, an oxygen atom, a sulfuratom, a carbonyl atom, a sulfonyl group, or a methylene group or similarlinkage; R¹ and R² are independently hydrogen, halogen, a hydrocarbyl orsubstituted hydrocarbyl, wherein hydrocarbyl is a monovalent hydrocarbonsuch as alkyl, cycloalkyl, aralkyl, or aryl and the substituent(s) is amonovalent moiety which is inert in the reactions used to prepare thepolymer; and R₃ is hydrogen, a hydrocarbyl or substituted hydrocarbylwherein hydrocarbyl is as defined previously and the substituent(s) isalso as defined previously. Examples of such substituents includehydroxy, cyano and halo moieties. Preferably, n is an integer from about10 to about 1000; x is 0.01 to 1.0; and y is 0 to 0.5.

[0042] The term “predominantly hydrocarbylene,” as used herein, means adivalent radical that is predominantly hydrocarbon, but which optionallycontains a small quantity of a heteroatomic moiety such as oxygen,sulfur, imino, sulfonyl, sulfoxyl, and the like.

[0043] The hydroxy-functional poly(amide ethers) represented by FormulaI may be prepared by contacting an N,N′-bis(hydroxyphenylamido)alkane orarene with a diglycidyl ether as described in U.S. Pat. Nos. 5,089,588and 5,143,998 (both incorporated herein by reference in their entirety).

[0044] The poly(hydroxy amide ethers) represented by Formula II may beprepared by contacting a bis(hydroxyphenylamido)alkane or arene, or acombination of 2 or more of these compounds, such asN,N′-bis(3-hydroxyphenyl) adipamide orN,N′-bis(3-hydroxyphenyl)glutaramide, with an epihalohydrin as describedin U.S. Pat. No. 5,134,218 (incorporated herein by reference in itsentirety).

[0045] The amide- and hydroxymethyl-functionalized polyethersrepresented by Formula III can be prepared, for example, by reacting thediglycidyl ethers, such as the diglycidyl ether of bisphenol A, with adihydric phenol having pendant amido, N-substituted amido and/orhydroxyalkyl moieties, such as 2,2-bis(4-hydroxyphenyl)acetamide and3,5-dihydroxybenzamide. These polyethers and their preparation aredescribed in U.S. Pat. Nos. 5,115,075 and 5,218,075 (both incorporatedherein by reference in their entirety).

[0046] The hydroxy-functional polyethers represented by Formula IV canbe prepared, for example, by allowing a diglycidyl ether or combinationof diglycidyl ethers to react with a dihydric phenol or a combination ofdihydric phenols using the process described in U.S. Pat. No. 5,164,472.Alternatively, the hydroxy-functional polyethers may be obtained byallowing a dihydric phenol or combination of dihydric phenols to reactwith an epihalohydrin by the process described by Reinking, Barnabeo andHale in the Journal of Applied Polymer Science, Vol. 7, p. 2135 (1963)(both the patent and journal article of this paragraph are incorporatedherein by reference in their entirety).

[0047] The hydroxy-functional poly(ether sulfonamides) represented byFormula V may be prepared, for example, by polymerizing an N,N′-dialkylor N,N′-diaryldisulfonamide with a diglycidyl ether as described in U.S.Pat. No. 5,149,768 (incorporated herein by reference in its entirety).

[0048] The poly(hydroxy ester ethers) represented by Formula VI may beprepared by reacting diglycidyl ethers of aliphatic or aromatic diacids,such as diglycidyl terephthalate, or diglycidyl ethers of dihydricphenols with, aliphatic or aromatic diacids such as adipic acid orisophthalic acid. These polyesters are described in U.S. Pat. No.5,171,820 (incorporated herein by reference in its entirety).

[0049] The hydroxy-phenoxyether polymers represented by Formula VII maybe prepared, for example, by contacting at least one dinucleophilicmonomer with at least one diglycidyl ether of a cardo bisphenol, such as9,9-bis(4-hydroxyphenyl)fluorene, phenolphthalein, orphenolphthalimidine or a substituted cardo bisphenol, such as asubstituted bis(hydroxyphenyl)fluorene, a substituted phenolphthalein ora substituted phenolphthalimidine under conditions sufficient to causethe nucleophilic moieties of the dinucleophilic monomer to react withepoxy moieties to form a polymer backbone containing pendant hydroxymoieties and ether, imino, amino, sulfonamido or ester linkages. Thesehydroxy-phenoxyether polymers are described in U.S. Pat. No. 5,814,373(incorporated herein by reference in its entirety).

[0050] The poly(hydroxyamino ethers) (“PHAE” or polyetheramines)represented by Formula VIII may be prepared by contacting one or more ofthe diglycidyl ethers of a dihydric phenol with an amine having twoamine hydrogens under conditions sufficient to cause the amine moietiesto react with epoxy moieties to form a polymer backbone having aminelinkages, ether linkages and pendant hydroxyl moieties. Examples ofpolymers of this type are described in U.S. Pat. No. 5,275,853(incorporated herein by reference in its entirety).

[0051] Thermoplastic phenoxy materials suitable for use in the preferredembodiments include those commercially available from PhenoxyAssociates, Inc. These hydroxy-phenoxyether polymers are preferably thecondensation reaction products of a dihydric polynuclear phenol, such asbisphenol A, and an epihalohydrin and have the repeating unitsrepresented by Formula IV wherein Ar is an isopropylidene diphenylenemoiety. A process for preparing these polymers is described in U.S. Pat.No. 3,305,528 (incorporated herein by reference in its entirety).

[0052] Phenoxy-type thermoplastics of Formulae I-VIII may be obtainedcommercially from Dow Chemical Company (Midland, Mich. U.S.A.). The mostpreferred hydroxy-phenoxyether polymers are the poly(hydroxyaminoethers) (“PHAE” or polyetheramines) represented by Formula VIII, such asXU19040.000L or BLOX 0005 available from The Dow Chemical Company.

[0053] The amount of hydroxy-phenoxyether polymer in the paper of thepreferred embodiments is generally selected to be effective to providethe paper with a desirable property such as increased sizing and/orstrength. Preferred amounts of hydroxy-phenoxyether polymer in the papermay be in the range of from about 0.01% to about 50%, more preferablyabout 0.1% to about 25%, even more preferably about 0.5% to about 20%,most preferably about 1% to about 10%, by weight based on total paperweight, depending on the particular application and the degree ofsizing, strength or other property desired.

[0054] The hydroxy-phenoxyether polymer used in the methods andmaterials described herein may comprise virgin material, recycled orpost-consumer material, or some combination of the two. It has beenfound that use of recycled hydroxy-phenoxyether polymer in thematerials, products, and methods described below results in a minorreduction of the advantageous properties which result from inclusion ofthe hydroxy-phenoxyether polymer, if any reduction occurs at all. Assuch, it is intended that hydroxy-phenoxyether polymer comprising someor all recycled polymer optionally be used in any of the methodsdescribed below, whether or not there is specific mention of the optionof its use in any given example or description.

[0055] The term “sizing,” as used herein, is a broad term and is used inits ordinary sense to include, without limitation, resistance topenetration by a liquid. The liquid in question may be aqueous ororganic in nature. For a particular liquid, sizing may be assessedqualitatively by observing the extent and rate at which a drop of liquidspreads through the paper after being placed on the surface of thepaper, by e.g., measuring the rate of spreading as a function of time.Various types of water, grease and aqueous liquids may be used to assesssizing, depending on the intended application for the paper. Forinstance, in a packaging application involving a greasy or oily food,the use of the grease or oil in question may be appropriate, whereasorange juice, milk or water may be more appropriate test fluids insituations where resistance to those liquids is desirable. In othersituations a more quantitative measure, such as a measurement of Cobbsizing, is appropriate. The Cobb test evaluates sizing in terms of theamount of liquid absorbed by the paper over a defined interval of timeand is typically reported as the weight of liquid absorbed in units ofgrams of liquid per square meter of paper. It is a well-defined methodknown to those skilled in the art, see e.g. TAPPI T 441 om-90 (1990).The lower the Cobb value, the better the sizing, and a decrease in Cobbvalue represents an increase in sizing.

[0056] Quantitative sizing tests also exist for oil and greaseresistance. For oil, these include the 3M Kit Test, which is identicalto TAPPI Useful Method 557. It consists of testing the paper withdroplets of increasingly aggressive mixtures of castor oil, toluene, andheptane to determine resistance to staining. Higher Kit numbers indicatebetter oil and grease resistance. For grease, these include TAPPI TestMethod T 454 om-89 (turpentine test for grease resistance of paper).This test consists of exposing the sheet surface to sand saturated withcolored turpentine for various periods of time. Longer periods ofexposure without staining indicates better grease resistance. Preferredpapers contain hydroxy-phenoxyether polymer in an amount that iseffective to provide the paper with improved resistance to water, oiland/or grease, as compared to a comparable paper.

[0057] When assessing water resistance, a preferred paper has anincrease in sizing that is manifested as a decrease in Cobb value ofabout 5% or more, as compared to a comparable paper. When assessing oilresistance, a preferred paper has in increase in sizing that ismanifested as an increase in the Kit value of about one or more, ascompared to a comparable paper. When assessing grease resistance, apreferred paper has in increase in sizing that is manifested as anincrease in the turpentine test value of about 5% or more, as comparedto a comparable paper. As used herein, a “comparable paper” does notcontain a hydroxy-phenoxyether polymer, but is in all other meaningfulrespects substantially identical to the paper containing thehydroxy-phenoxyether polymer that is the subject of the test. Forinstance, if a comparable paper has a Cobb value of 100 g/m², then apaper having an increase in sizing that is manifested as a decrease inCobb value of about 5% or more has a Cobb value that is(100−(100×0.05))=95 g/m² or less. Preferably, the paper has a Cobb valueof 100 g/m² or less, more preferably 40 g/m² or less.

[0058] Other tests may be used to assess sizing. For instance, thoseskilled in the art are aware of the well known Hercules Sizing Test(HST), which is TAPPI Test Method T530 pm-89 Size test for paper by inkresistance (Hercules method), and will select the test that is mostappropriate in accordance with principles understood by those of skillin the art.

[0059] Hydroxy-phenoxyether polymer may be incorporated into paper bythe various methods described herein to provide that paper with anincrease in strength. The term “strength,” as used herein, is a broadterm and is used in its ordinary sense to mean, without limitation,resistance to rupture or deformation under an applied load. It mayinclude one or more of the following and may be measured dry or wet:tensile strength, compressive strength, tear resistance, burst strength,stiffness (flexural modulus, also referred to herein as flexuralstrength), tensile energy absorption, (TEA), surface strength, abrasionresistance, folding resistance, and ply bond strength. Preferably, thepaper has an increased dry tensile strength and/or an increased wettensile strength of about 5% or more, more preferably 10% or more.Preferably, the paper has an increased flexural strength (or modulus)and/or an increased wet flexural strength (or modulus) of about 5% ormore, more preferably 10% or more. In a particularly preferredembodiment, corrugated paper has an increased wet flexural strength ofabout 5% or more, more preferably 10% or more. This increase in the wetflexural strength of corrugated paper may be accomplished byincorporating hydroxy-phenoxyether polymer into the linerboard and/orfluting paper from which the corrugated paper is made. The magnitude ofan increase in strength may be determined by comparison to a comparablepaper as defined above, using test methods well known to those skilledin the art.

[0060] Hydroxy-phenoxyether polymer may also be used to improve theproductivity of the papermaking process. Preferably, thehydroxy-phenoxyether polymer is incorporated into a wet paper web in anamount effective to increase wet web strength. Most preferably, thisincrease in wet web strength results in decreased line breaks on the wetend of the machine, leading to increased paper mill productivity.

[0061] For foods such as baked goods, it is often preferable for thepackaging to have a certain degree of “breathability” or permeability inorder to allow the moisture content to change in an amount that iseffective to preserve freshness and crispness. However, staleness of thebaked goods may result if the packaging is overly permeable. Theinventors have found that the permeability of the paper or paperboardmay be adjusted by controlling the amount of hydroxy-phenoxyetherpolymer incorporated therein. Relative to comparable paper as definedabove, the paper preferably exhibits lower permeability to gases such asoxygen, nitrogen, carbon dioxide, and/or water vapor. Most preferably,the amount of hydroxy-phenoxyether polymer in the paper is effective toallow the desired degree of gas permeability, depending on theparticular application. For instance, for some food packaging andnon-food application such as ream and roll wrap, relatively high levelsof resistance to moisture (water vapor) and oxygen transmission arefrequently preferred, and may be obtained by incorporatinghydroxy-phenoxyether polymer. Water vapor permeability may be measuredby TAPPI Test Method T 523 om-93 Dynamic measurement of water vaportransfer through sheet materials. Results are typically reported inunits of grams per square meter per day (gsm/day). Preferred values tendto depend on the application, e.g., about 15 gsm or less for bakeryboxes, about 10 gsm or less for ream paper, and about 5 gsm or less fordetergent boxes. Permeability of oxygen may be measured by a Moconinstrument in units of cubic centimeters per square meter per day(cm³/m²/day). Preferred values tend to depend on the application, e.g.,about 250 cm³/m²/day or less for keep fresh boxes, about 200 cm³/m²/dayor less for bag paper, and about 100 cm³/m²/day or less for barrierpaper.

[0062] The paper described herein may be shaped, processed orincorporated into semi-finished or finished manufactured items such aswriting paper, drawing paper, paper towels, tissues, containers (e.g.,paper bags, paper boxes, cardboard boxes, mailing tubes, file folders),photo paper, glossy paper, cardboard, corrugated cardboard, disposablediapers, adhesive labels, honeycomb structures (e.g., cellularstructures having open or closed cells of one or more shapes, includingwithout limitation hexagonal, polygonal, and/or rounded shapes),sandpaper, and packaging material, by processes and methods generallyknown to those skilled in the art.

[0063] In a preferred embodiment, a process for making paper isprovided. A preferred process involves making paper by using an amountof a hydroxy-phenoxyether polymer that is effective to provide the paperwith an increase in sizing or strength. The hydroxy-phenoxyether polymermay be incorporated into the paper at any convenient point or pointsduring the process of making the paper or by treating or coating theformed paper.

[0064] An illustrative, non-limiting example of a flow diagram for atypical papermaking process in shown FIG. 3. FIG. 3 also identifiestypical equipment used at the various states of the process. In such aprocess, bales of dry wood pulp or waste paper may be pulped in ahydrapulper to form a pulp slurry (fiber dispersion 300) with aconsistency in the range of about 2 to about 30% depending on the pulperand the manufacturing process. The pulp may then be refined to enhancethe strength and bonding properties of the cellulosic material. Refiningmay be carried out at a range of consistencies depending on the refinersused and therefore may involve dilution of the pulp slurry. Afterrefining, the pulp slurry is usually screened and cleaned to removeimpurities, then passed to blending tanks where chemical additions aremade. This is one point where the hydroxy-phenoxyether polymer may beintermixed with the pulp slurry.

[0065] Typically, the next stage of papermaking is the sheet forming anddraining process 310. The sheet forming process suitably consists ofseven distinct sections: Headbox (or flowbox), wire section, presssection, dryer section, size press, calendar and reel up. The headbox isa collecting box for dilute pulp slurry. A narrow aperture runningacross the width of the box allows the pulp slurry to flow onto the wirewith the cellulosic material being distributed evenly over the width ofthe paper machine. The wire is often a woven plastic mesh conveyer beltand as the pulp slurry flows from the flow box onto the wire the waterdrains away initially by gravity and then aided by suction to leave apaper web on the wire. This is one point where the hydroxy-phenoxyetherpolymer solution or dispersion could be intermixed with the paper web,e.g., by spraying onto the web. The amount of the polymer entrained inthe web usually depends on the temperature and moisture content of theweb, the solids content and viscosity of the polymer solution ordispersion, the speed of the machine and the pressure of the rolls atthe press section.

[0066] In the press section 320, the paper web, typically supported on afelt, passes through a series of rollers, which tend to consolidate theweb and remove more water. The web then passes to the dryer section 330,which consists of a large number of heated ‘cans’ or cylinders toevaporate the remaining water. Surface sizing 340 can be conducted witha size press, which may be located part way down the drying section, isanother point where the hydroxy-phenoxyether polymer solution ordispersion may be intermixed with the wet paper or paper web. After thedrying section 350, on many machines there is a calender stack 360. Herea series of polished rollers consolidate and polish or glaze the surfaceof the paper giving a smoother finish. Calendar sizing may also be usedto size the paper with the hydroxy-phenoxyether polymer. Finally, thefinished paper is reeled up 370 for transport to further processing orfor slitting down into smaller reels or individual sheets.

[0067] The papermaking process also offers the potential for theapplication of the hydroxy-phenoxyether polymer to single ply ormulti-ply paper. Multi-ply paper may be produced with the polymerlaminated between the plies or, as in the case of single plies, with thepolymer contained throughout the whole paper sheet. Multi-ply paper andboard offers good product versatility especially with the application ofhydroxy-phenoxyether polymer. Paper/board can be produced with the pliesmade from the same pulp slurry and with the same basis weight, or theplies can be from different pulp slurries and/or have different basisweights. Multi-ply sheets are generally made in a similar manner tosingle ply sheets, but each ply tends to have its own headbox and wiresection with the two or more plies meeting in the press section forconsolidation and bonding. Intermixing hydroxy-phenoxyether polymer mayenhance this bonding, e.g., providing increased ply bond strength, andmay increase the strength and resilience properties of the paper orpaperboard.

[0068] The term “molding,” as used herein, is a broad term and is usedin its usual sense to include, without limitation, various processes forshaping paper or concentrated pulp slurries to form desired shapes suchas sheets or three-dimensional objects. The products resulting fromthese processes may be referred to herein as being “molded” products.For instance, pulp molding may be used to make the paper of thepreferred embodiments. As an example of pulp molding, also known as dipmolding, a wire mold is formed into the shape of the object in question,e.g., an egg carton. The mold unit is attached to a vacuum source withan intermediate separator or trap, such that when the mold is dippedinto a pulp slurry, water is drawn through the wire and deposits a paperweb on the surface of the wire in the shape of the object. Whensufficient thickness of cellulosic material is built up on or in themold, the mold is withdrawn from the pulp slurry and air may then bedrawn through the wet web to partially dry it. The formed shape is thentransferred to a support and dried by e.g., passage through an oven,infrared drying unit or similar drying system to produce the finalarticle. In some instances, e.g., the production of smooth, glazedcontainers, the wet article may be inserted into a polished die andexpanded against the heated walls of the die by an inflatable rubberbladder. The bladder may then be deflated and the shape removed from thedie for final drying.

[0069] The hydroxy-phenoxyether polymer may be added to the pulp slurrybefore molding, in the same manner as it may be added to the pulp slurrybefore forming on a paper machine. Alternatively, it may be added byimpregnation of the dried article by dipping the article into a polymersolution or dispersion with or without the application of pressure orvacuum to the article to force the polymer into the interior of thecellulosic mass. The article may then be dried in the usual manner togive a product with superior properties, e.g. improved water and oilresistance, improved toughness, and improved compressive and tensilestrength.

[0070] In preferred embodiments, the hydroxy-phenoxyether polymer isincorporated into the paper by intermixing with: the pulp slurry, thepaper web or wet paper sheet on the paper or paperboard machine, formedpaper plies to form multi-ply paperboard or paper laminate, the paper orpaper web by surface addition at the size press, paper or board byon-machine surface coating or off-line in another process, etc. The term“intermixing,” as used herein, is a broad term that that is used in itsordinary sense to include, without limitation, all manner of applying,mixing, coating and/or spraying the hydroxy-phenoxyether polymer (ormixture containing the polymer) with or onto cellulosic material to forman admixture that comprises the polymer and the cellulosic material.Thus, the resulting admixture may but need not be a heterogeneous orhomogeneous physical mixture of cellulosic material andhydroxy-phenoxyether polymer. The admixture may be in the nature of alayer or coating of hydroxy-phenoxyether polymer on the cellulosicmaterial. The term “cellulosic material,” as used herein, is a broadterm that is used in its ordinary sense to include, without limitation,all manner of cellulose-containing compositions, including pulp slurry,the paper web that is formed during the papermaking process, theconcentrated pulp slurry used in the pulp molding process, wet paper,and dry paper.

[0071] In a preferred embodiment, paper is made by a process comprisingproviding a pulp slurry or paper web, providing a solution or dispersioncomprised of a hydroxy-phenoxyether polymer, intermixing the solution ordispersion with the pulp slurry or paper web to form an admixture, andforming paper from the admixture, wherein the hydroxy-phenoxyetherpolymer is used in an amount that is effective to provide the paper withan increase in sizing or strength. For sizing, preferred amounts ofpolymer may be in the range of from about 0.01% to about 10%, morepreferably about 0.1% to about 5%, by weight based on total weight ofpaper. For strength, preferred amounts of polymer may be in the range offrom about 0.1% to about 50%, more preferably 1% to about 30%, by weightbased on total weight of paper. In more preferred embodiments, thehydroxy-phenoxyether polymer is intermixed with the cellulosic materialby forming a solution or dispersion comprised of the polymer, and addingit to the pulp slurry, paper web, or formed paper by preferredtechniques such as by mechanical mixing with the aqueous pulp slurry(with or without pH adjustment) and/or spraying or coating the paper webor formed paper.

[0072] The hydroxy-phenoxyether polymer may also be applied in a foamcoating process. For example, a foam comprised of hydroxy-phenoxyetherpolymer may be ‘sandwiched’ between two or more paper layers to producea laminated structure. Impregnation of a pre-dried sheet makes moreefficient use of the natural bonding properties of the cellulosicmaterial and permits some control of the distribution of polymer throughthe thickness of the sheet. This may be done either at the size-press oras an off-line process.

[0073] Preferred hydroxy-phenoxyether polymers are soluble in aqueousacid and such polymer solutions may be intermixed with the cellulosicmaterial. An example of a preferred polymer is polyetheramine. A mostpreferred polymer is available from Dow Chemical under the tradenameBLOX®. A polymer solution may be prepared by stirring or otherwiseagitating the hydroxy-phenoxyether polymer in a solution of water withacid, preferably acetic or phosphoric acid. The resulting polymersolution may be intermixed with cellulosic material to form anadmixture. The admixture may then be processed in the usual manner toeventually remove the excess water and form the paper. In a preferredembodiment, the acid concentration in the polymer solution is preferablyin the range of about 5%-20%, more preferably about 5%-10%, by weightbased on total weight. In other preferred embodiments, the acidconcentration may be below about 5% or above about 20%, depending on thetype of polymer and its molecular weight. The amount of dissolvedpolymer in a preferred embodiment is about 0.1% to about 40%. A uniformand free-flowing polymer solution is preferred for application at thewet end. Most preferably, a 10% polymer solution is prepared bydissolving the polymer in a 10% acetic acid solution at 90° C. and whilestill hot the solution diluted with 20% distilled water to give an 8%polymer solution. At higher concentrations of polymer, the polymersolution tends to be more viscous.

[0074] A polymer solution may be optionally neutralized by the additionof a base before or after intermixing with cellulosic material toprecipitate the polymer, forming a polymer dispersion. A polymerdispersion may also be formed by intermixing small particles of polymerwith a liquid, preferably an aqueous liquid and preferably by high shearmixing techniques known to those skilled in the art. Depending upon thespecifics of the method used to form the paper, it may be desirable forthe polymer solution or dispersion to have certain qualities such as aparticular degree of dissolution/precipitation, larger or smallerprecipitate particle size, or a pH in a certain range. These propertiescan, in part, be controlled by the degree of neutralization, the mannerin which neutralization is carried out, and the place in the process inwhich neutralization is carried out.

[0075] Neutralization is preferably performed by the addition of astrong base (alkaline) material such as caustic soda (sodium hydroxide),or potassium hydroxide to the medium containing the polymer. The degreeof neutralization may be used to control the degree of precipitation ofthe polymer from the solution, with the amount of precipitationincreasing as more alkali is used. If sufficient alkali is added, thesolution eventually becomes a dispersion of polymer particles in thesolution. The solution or admixture need not be fully neutralized priorto processing; it can be partially neutralized. A higher degree ofprecipitation may be desirable in some embodiments, as there may be agreater degree of adhesion between polymer and the cellulosic materialswhen the polymer molecules have aggregated to the point of no longerbeing dissolved. Thus, in preferred embodiments, the process of makingpaper comprises adjusting the pH of the admixture to precipitate a leasta portion of the hydroxy-phenoxyether polymer, most preferably in thepresence of the cellulosic material prior to forming a web. Mostpreferably, the process comprises adjusting the pH of the admixture tobe in the range of about 4 to about 7.

[0076] The manner in which neutralization is carried out may also affectthe result. If the alkali used for neutralization is added slowly, thedispersion which forms tends to be fairly uniform and of a moderate tosmall particle size. On the other hand, if all of the alkali is addedquickly, the dispersion which forms tends to have a greater variety ofparticle sizes as well as having many more larger size particles ascompared to the slowly neutralized material. Therefore, the speed ofalkali addition may be used to promote a particular particle size orparticle size distribution. Preferably, the dispersion has a numberaverage particle size of about 500 microns or less, more preferably 100microns or less, most preferably 10 microns or less.

[0077] Precipitation/neutralization may take place prior to intermixingthe polymer solution/dispersion with the cellulosic material, or it maybe done while the polymer is in contact with the cellulosic material.Also, it may be desired to perform the neutralization at a particularpoint in the process for reasons including, but not limited to, theminimization or maximization of the length of time that a particularprocess takes, the optimization of the viscosity of the medium at one ormore places in the process, or to prevent certain equipment frombecoming exposed to material that falls above or below a particular pH.Materials having a high or low pH may etch, dissolve, or otherwise harmor degrade certain equipment or materials used in the papermakingprocess. Dispersions tend not to be as free-flowing as polymersolutions, and this difference may be more notable if the cellulosicmaterial is already in contact with the polymer.

[0078] Preferably, the polymer is added at either the pulp slurrypreparation stage or at the web forming stage. At the pulp slurrypreparation stage, the polymer and base (preferably potassium or sodiumhydroxide) may be added together, whereas at the wet sheet formingstage, the polymer is preferably added after the base. The mostpreferred point of polymer addition depends on the viscosity of thepolymer solution, its retention and bonding potential at different pulpconsistencies (the consistency at the pulp slurry preparation stagetends to be higher than at the web forming stage) and the papermachine's operating procedure.

[0079] Maximum retention of the polymer on the cellulosic material isusually preferred to minimize loss of polymer. Retention is preferablymaximized at the isoelectric point and decreases as the pH is lowered.Although retention may be poorer at low pH values, both wet and drystrength tend to be high. As pH is increased strength tends to decreaseowing to aggregate formation and then tends to increase again as polymerretention increases. Preferably, the polymer particles and thecellulosic material are oppositely charged in order to achieve goodretention. A cationic or amphoteric adjuvant may be added to assistprecipitation of the polymer onto the surface of the cellulosic materialand by adjusting the pH to the electrokinetic point at which the polymeris preferably deposited. Examples of such adjuvants include alum, sodiumaluminates, zirconium salts, polyamines, poly(diallyldimethylammoniumchloride) (polyDADMAC), poly(ethyleneimine) (PEI), diamine- anddicyanoamide polymers, polyacrylamide copolymers, cationic starches,polyamide-epichlorohydrin resins, and aminoplast resins.

[0080] The paper may be formed by intermixing a solution or dispersionof polymer with a paper web or formed paper. Various methods are knownin the art. For example, a polymer solution or dispersion may be sprayedonto one or more sides of the web or paper. Other methods include:applying a coating of dispersion or solution on one or more sides usinga blade coater; coating or impregnating by placing the dispersion orsolution onto one or more sides of the paper or web and allowinggravity, pressure, or vacuum to draw the paper to the polymer; and useof size pressing technology, such as is known in the art, to coat apaper or web with a dispersion or solution of polymer. As discussedabove, the application of the solution or dispersion may be done with orwithout neutralization, and if neutralization is employed, as ispresently preferred, it may be partial or complete and may take place atany step in the process.

[0081] Beater or wet end addition methods are preferably employed thatinvolve adding the polymer solution to the pulp slurry, preferablyresulting in pH of about 4 to about 5, then adding an alkali, preferablyNaOH, to bring the pH above 6 to precipitate the polymer onto thecellulosic material. The polymer, preferably polymer solution, may alsobe added to the dilute loop, preferably at the basis weight valve, alongwith alkali in the tray water, preferably NaOH, to control headbox pH tobe in the range of about 6.0 to about 6.5.

[0082] In the wet-web saturation process, which may be used for additionof polymer to web in relatively high concentration (e.g., 35-50% oftotal weight), the process preferably involves three strategies: waterremoval by wet pressing; polymer saturation of the wet web by capillaryand hydrostatic forces; and redistribution and removal of excesspolymer.

[0083] Factors influencing the web consolidation and the percentage ofpolymer in web include the capacity of the web to absorb polymer, therate of penetration of the polymer into the web, and wet pressing of theweb to a level of dryness (preferably <50%) before saturation with thepolymer.

[0084] Additional components may also be added to thehydroxy-phenoxyether polymer solution or dispersion to enhance thepackaging properties and/or appearance of the paper. Two categories ofadditives are preferred, process aids and product additives. Examples ofprocess aids are as rheology modifiers or thickeners, calenderlubricants, and biocides. Examples of product additives are opticalbrightening agents, crosslinking agents, plasticizers, dyes, fillers,anti-static agents, anti-slip or anti-tack agents and flame retardants.Other materials e.g., plastics, metals, wood, ceramic, minerals, glass,carbon, etc., in various forms, e.g., long fiber, short fiber, wovenfiber, powder, etc., may be added to the polymer, and may add to or takethe place of cellulosic materials. Process additives may be used toimprove the efficiency of the coating operations, e.g., by controllingcoatweight and uniformity or by preventing microbial attack. Productadditives may be used to improve the performance of the product. Forexample, crosslinking agents tend to increase the rigidity andwater-resistance of the product. They include materials such asaminoplast, epihalohydrin or glyoxal resins and inorganics such aszirconium compounds. Plasticizers may include low T_(g) (glasstransition temperature) acrylic or vinyl resins to improve flexuralproperties.

[0085] Further details concerning materials comprised of hydroxyphenoxyether polymers are unnecessary to discuss here and are disclosedin Assignee's copending application entitled HYDROXY-PHENOXYETHERPOLYMER/FIBER COMPOSITES AND FOAMS, application Ser. No. ______[AttorneyDocket No. APTLTD.020A], filed on the same date as the presentapplication, the entirety of which is hereby incorporated by reference.

[0086] The order and manner of addition of the ingredients is preferablycontrolled to avoid gross precipitation of the hydroxy-phenoxyetherpolymer from solution or sudden increases in viscosity. A high-shearmixer is preferably used, but caution should preferably be exercised toavoid shearing the polymer to the extent that the viscosity andeffectiveness of the coating are reduced. The additives should also becompatible with the acidic nature of the dispersion or solution.

[0087] Both standard ‘puddle’ size presses and metering size presses maybe used for intermixing. Puddle size press are preferably used on slowerpaper machines and tend to give strength improvements together with oiland grease resistance. A non-limiting schematic diagram illustratingvarious aspects of a typical “puddle” size press 400 is shown in FIG. 4.In such a puddle size press, a paper web 410 is fed between a rubbercovered roll 420 and a hard roll 430, by way of turn rolls 440 and 445,and a sizing composition is supplied by sprays 450, forming a puddle 460between paper web 410 and rubber covered roll 420.

[0088] Metering size presses tend to give less penetration, thereforeless strength improvement but higher film forming and barrierperformance. They are often used on larger, higher speed machines. Anon-limiting schematic diagram illustrating various aspects of a typicalmetering size press 500 is shown in FIG. 5. In such a metering sizepress, a paper web 510 is fed between a roll 520 and a roll 530, by wayof a turn roll 540 and an air turn 545, and a sizing composition isapplied to the hard roll 530 by coating head 550, and also to rubbercovered roll 520 by coating head 551, which roll 530 and roll 520 inrotating supply the sizing to the paper web 510. Roll 520 and roll 530are preferably coated with an elastomer, with the elastomer on roll 520being preferably softer than the elastomer on roll 530. Size presstreatment may be used to provide a single functional coat or aground-coat for further coating applications later as in the productionof base stock for silicone release papers. Platy clays or similarminerals may be incorporated in the polymer formulation to improvecost-effectiveness of the coating.

[0089] Paper strength is often influenced by the bonding between thecellulosic material and the polymer. Factors which influence theadhesion or adhesive bonding between the cellulosic material and polymerinclude: wetting of the surfaces; solidification (to provide resistanceto shear); deformability (to reduce stress concentration); intimatecontact between surfaces (such as is preferred for chemical bonding);diffusion of macromolecules of bonding materials within the adhesivezone; temperature (adhesion increases near T_(g), and lowering T_(g)'sby e.g., adding water, may increase adhesion within the composite).Adhesion may also be influenced by the capability of the polymermolecules to penetrate into the cracks and pores of the cellulosicmaterial. The effective diameter of the polymer may also affect itspenetration ability.

[0090] Adhesion or bonding may be improved by improving the surfacereactivity of the cellulosic material. Preferably, this may be done bychemical or electrochemical means. For example, one may increase theionic character of the cellulosic material. Ionic bonding with thecellulosic material may be helpful because ionic bonds are rapidlyformed in aqueous systems and need no further curing, and compoundscapable of forming ionic bonds are often soluble in water, the preferredsolvent for the solutions and dispersions herein. Furthermore, ionicbonds are usually reversible, and these electrostatic attractions cantake place over a greater distance than covalent bonds. Reactiveproducts known in the art may be used to create anionic sites on thecellulosic material. Cationic polyacrylamide, polyethylene amine,cationic starch, cationic guar (galactomannan) gum, and chitosan (fromsea shells) are examples of preferred products used to enhance paperstrength, and may function by increasing bonding.

[0091] Additionally, other methods may be used such as treatment withwetting agents, surfactants, and acids or bases. Polymers having goodwetting capability towards the cellulosic material can, during thedrying process, enhance strength as the polymer comes into closercontact with the cellulosic material. Other factors that may influencebonding are the particle size, viscosity, stabilizer level, and presenceof functional groups like carboxyl groups within the polymer or on thesurface of the cellulosic material. Surfactants may improve bonding byhelping to reduce surface tension or increase the hydrophobicity of thecellulosic material. This in turn allows the building of a bulkier webat a given level of water. POLYWET™ surfactants, available commerciallyfrom Peach State Labs, Inc., Rome, Ga., USA, may be used to improvestability and adhesion.

[0092] When the processes described herein are used on formed paper, acoated paper may result. Thus, a process for coating paper is alsoprovided, comprising providing a paper, providing a solution ordispersion comprised of a hydroxy-phenoxyether polymer, applying thesolution or dispersion to at least a portion of the paper to form a wetpaper, and drying the wet paper to form a coated paper. The solution ordispersion may be applied using any convenient technique describedherein for intermixing a polymer with a paper web or formed paper.Drying may be accomplished by simple evaporative techniques, or may beencouraged by known methods such as by heating the wet paper.Preferably, for processes described herein that involve drying, thedrying temperature is near the melting or glass transition temperatureof the hydroxy-phenoxyether polymer. In preferred embodiments, thecoated paper has a Cobb value of about 100 g/m² or less, preferablyabout 50 g/m² or less. Preferably, the coated paper is comprised of fromabout 0.1% to about 50%, more preferably about 1% to about 30%, evenmore preferably about 2% to about 20%, most preferably about 5% to about15%, by weight based on total coated paper weight, of thehydroxy-phenoxyether polymer.

[0093] Paper may be coated using a variety of known methods, including:roll, reverse roll, gravure, dip saturation, fountain, blade, rod, andair knife. A non-limiting schematic illustrating various types of rollcoaters is shown in FIG. 6. The simplest form of roll coater has a paper600 contacting a roll 610 dipping into the polymer dispersion orsolution 630 contained in a pan 640. This type of system is verysensitive to changes of speed and the level of the liquid in the pan.The addition of a transfer roll 650 tends to smooth out the liquid filmon the lower roll and presents a more uniform coating to the paper.Changing the gap between the rollers controls the thickness of theliquid film transferred to the sheet. The liquid film may be sheareddown further by using a reverse-roll applicator 660 in which thedirection of rotation of the transfer roll is opposed to the directionof travel of the paper or board substrate. Coat weights between 5 and 20g/m² per side are preferred.

[0094] For gravure coating the engraved cells on the surface of thegravure roll 670 pick up the solution or dispersion, with the excessbeing doctored off by a blade. This enables the gravure roll to apply aprecise coating thickness regardless of variations in the substratethickness typically laying down coat weights of between 0.5 and 8 g/m².The coating solution or dispersion is preferably of a fairly lowviscosity.

[0095] The paper is typically supported by a backing roll at the pointof contact with the transfer roll. The transfer, reverse roll andgravure coaters usually pre-meter the polymer dispersion or solutionbefore application. In the case of blade, air knife and rod coaters, themetering process usually takes place after application. A non-limitingschematic illustrating various aspects of blade coater 700 and air knifecoater 750 is shown in FIG. 7.

[0096] Air knife, blade and rod coaters may use either a roll coater 710or a fountain applicator 760 to apply an initial layer of coating to thecoated sheet 720 or 721, then employ a separate metering method forcontrol of coatweight. The fountain applicator 760 is a slit or channelthrough which the dispersion or solution is forced in order to ply uponand be picked up by the passing sheet surface.

[0097] In air knife coating the polymer dispersion or solution isapplied in excess to the paper substrate 721, then a backing roll 770 isused to carry the paper to an air curtain 780 which is used to removethe excess as well as level the coating on the sheet. The excess can berecovered in a catch tray 790. The amount of coating applied is governedby air pressure, angle of the air jet, machine speed and resin solids.In blade coating, a backing roll 730 is used to carry the paper 720 to aflexible steel blade 740 which acts as the metering device. Thecoatweight then depends on blade angle and pressure, solution ordispersion solids, machine speed as well as substrate roughnesscompressibility and permeability.

[0098] In rod coating, the excess solution or dispersion is removed byeither a smooth or a wire wound rotating rod (Mayer bar). The amount ofcoating applied is governed by wrap around the applicator roll, wirediameter around the rod, web tension and coating solution or dispersionviscosity and solids. A further method of application is cast-coating inwhich a layer of polymer is coated onto a smooth, heated cylinder thentransferred in a semi-dry state to the surface of the paper. Suchmethods are commonly used when a very smooth, glossy surface is appliedbut operate at slower speeds than blade coating, Additives such ascasein may be used to obtain desired bulking and release properties inthe cast coating. Short-dwell coaters combine the application andmetering stages in one unit. A non-limiting schematic illustratingvarious aspects of a simple short dwell coater 800 is shown in FIG. 8.Short dwell coaters are well known to those skilled in the art, seee.g., U.S. Pat. No. 4,250,211, which is hereby incorporated by referencein its entirety.

[0099] Other methods of applying the polymer solution or dispersion tothe paper include spraying through fine nozzles on a spray beam or usingan air-jet sprayer as in paint application. This method limits solutionsolids and requires high levels of filtering, but is appropriate forspraying polymer dispersions between the plies of a multiply sheet as inpaperboard production. Foam addition is another possibility. A foamgenerator and applicator system may be used, along with a foam buildersuch as a protein or surfactant blend. One or more of the above coatingmethods may be used.

[0100] In many cases thickening agents or rheology modifiers are used toimprove the coverage and uniformity of the coating. The performance ofhydroxy-phenoxyether polymer as a barrier coating may be improved by theaddition of platy clays, preferably at a level below the criticalpigment volume concentration. After coating, the coated paper may becalendered to improve surface smoothness.

[0101] Preferred embodiments provide laminates and processes for makingthem. As used herein, “laminate” is a broad term that is used in itsusual sense to encompass layered structures, here formed from a layer ofpaper, a layer of a solid material such as a second paper or non-papermaterial, and a hydroxy-phenoxyether polymer. The polymer may be aseparate layer and/or may be contained within one or more of the paperlayers, and preferably serves to bond one or more of the layers to oneanother. The solid material may be virtually any material includingpaper, metal, foam, e.g., plastic foam, wood, polymer e.g.,thermoplastic polymer, thermoset polymer, filled polymer (e.g., containsfibers or particles of organic or inorganic filler), glass, stone,concrete, and ceramic. A preferred laminate is comprised ofhydroxy-phenoxyether polymer, at least one layer comprised of paper, andat least one layer comprised of a second paper or a solid non-papermaterial. Preferably, the laminate is comprised of from about 1% toabout 50%, more preferably about 2% to about 30%, even more preferablyabout 3% to about 20%, most preferably about 5% to about 15%, by weightbased on total laminate weight, of the hydroxy-phenoxyether polymer.

[0102] A preferred laminate displays synergism as compared to theindividual components of the laminate. The term “synergism,” as usedherein, is a broad term and is used in its ordinary sense to includeinteractions between parts that produce a result that is greater thanthe sum of the individual effects. For instance, a preferred laminatecan display synergism by exhibiting a physical property which is greaterthan would be expected based on the rule of mixtures, on a weight basis.More preferably, a laminate displays synergistic strength, e.g., hasgreater strength, most preferably flexural strength, than the sum of thecorresponding strengths of each of its individual components, adjustedfor the weights of the components in the laminate.

[0103] A preferred laminate is further comprised of additional materialsor fillers, more preferably a fibrous materials. Preferred fibrousmaterials include plant fibers made from wood pulp, cotton fibers, hemp,bagasse, abaca, flax, southern pine, southern hardwood fibers,cellulose, wheat, starch, modified starch, chitin, chitosan, keratin,cellulose acetate, cellulose materials derived from agriculturalproducts, gluten, nut shell flour, wood flour, corn cob flour, guar gum,and mixtures thereof.

[0104] A preferred embodiment provides a laminate that is less permeableto gases and water vapor, as compared to a comparable laminate. As usedherein, a “comparable laminate” does not contain a hydroxy-phenoxyetherpolymer, but is in all other meaningful respects substantially identicalto the laminate containing the hydroxy-phenoxyether polymer that is thesubject of the test. For instance, a preferred laminate having athickness of one millimeter (mm) and comprised of a 0.4 mm first paperlayer, a 0.4 mm second paper layer and a 0.2 mm hydroxy-phenoxyetherpolymer layer is less permeable to gases and water vapor than acomparable laminate comprised of a 0.5 mm first paper layer and a 0.5 mmsecond paper layer but without the hydroxy-phenoxyether polymer. Theinventors have found that the permeability of a laminate may be adjustedby controlling the amount of hydroxy-phenoxyether polymer incorporatedtherein. Relative to a comparable laminate as defined above, thelaminate preferably exhibits lower permeability to gases such as oxygen,nitrogen, carbon dioxide, and/or water vapor. Most preferably, theamount of hydroxy-phenoxyether polymer in the laminate is effective toallow the desired degree of gas permeability, depending on theparticular application, as discussed elsewhere herein. Water vapor andgas permeability may be determined by methods known to those skilled inthe art, as discussed elsewhere herein.

[0105] A preferred laminate is comprised of an amount of ahydroxy-phenoxyether polymer that is effective to provide the laminatewith an increase in sizing, preferably as manifested by an increase inresistance to water, oil and/or grease as compared to a comparablelaminate. For applications where water resistance is desirable, theincrease in sizing is preferably manifested as a decrease in Cobb sizingof about 5% or more, as compared to a comparable laminate. Forapplications where oil resistance is desirable, the increase in sizingis preferably manifested as an increase in the Kit value of about one ormore, as compared to a comparable laminate. For applications wheregrease resistance is desirable, the increase in sizing is preferablymanifested as an increase in the turpentine test value of about 5% ormore, as compared to a comparable laminate.

[0106] Preferably, the process for forming the laminate proceeds bypressing together one or more of the solid materials in such a way as toallow the hydroxy-phenoxyether polymer to at least partially bond thelayers together to form a laminate. More preferably, the processcomprises bringing paper into contact with a solid material, in thepresence of a solution or dispersion comprised of a hydroxy-phenoxyetherpolymer to form a wet laminate, followed by drying. The paper may be awet paper or a coated paper as described herein. If the paper is alreadywet with the solution or dispersion comprised of a hydroxy-phenoxyetherpolymer, then further amounts of polymer solution or dispersion may beused but are not required. More preferably, the process comprisesforming a wet laminate by bringing the wet paper into contact with asolid material, then drying said wet laminate to form a laminate,optionally with pressure to create a better bond between the layers.Even more preferably, the process comprises forming a wet laminate bybringing a coated paper into contact with a solution or dispersioncomprised of a hydroxy-phenoxyether polymer, and optionally into furthercontact with another paper or non-paper material, then drying the wetlaminate to form a laminate, optionally with pressure to create a betterbond between the layers. Pressure is preferably applied by running thelaminate between rollers. Multiple layers may be formed by repeating theprocess and/or by bringing together multiple layers simultaneously.

[0107] Coating processes as described herein may also be used to applydispersions of hydroxy-phenoxyether polymer to the surface of paper orboard for the purpose of laminating it to another sheet. Sheets ofseveral layers may be built up to provide feedstock for folding cartons,liquid packaging and pouches. The hydroxy-phenoxyether polymer may alsobe applied between the layers as a foam composition instead of by acoating process. The individual sheets or plies of the laminate maythemselves be pretreated with hydroxy-phenoxyether polymer by any of themethods outlined herein. In this way a multi-ply composite structure maybe built up with a relatively high polymer content, suitable forthermo-plastic forming, e.g., for trays and inserts.

[0108] Interlayer-addition of hydroxy-phenoxyether polymer by coating orfoam application may also be used in the production of spirally woundpaper tubes, cores and containers. The hydroxy-phenoxyether polymer mayact as both inter-layer adhesive and reinforcing agent to improvestrength and rigidity.

[0109] Additional details regarding laminates and coated papers areunnecessary to discuss here and are disclosed in Assignee's copendingapplication entitled LAMINATES AND COATED MATERIALS COMPRISINGHYDROXY-PHENOXYETHER POLYMERS, application Ser. No. ______ [AttorneyDocket No. APTLTD.019A], filed on the same date as the presentapplication, the entirety of which is hereby incorporated by reference.

[0110] In preferred embodiments, the paper is readily recyclable. Inembodiments where the hydroxy-phenoxyether polymer is soluble in aqueousacid, recycling may be facilitated by contacting the paper with aqueousacid to dissolve the polymer, then filtering off the residual cellulosicmaterial. The polymer may then be recovered from the solution byprecipitation with base to form a dispersion, followed by separationusing known techniques e.g., decantation, filtration, centrifugation,etc., or the dispersion may be used directly in the process for makingpaper as described elsewhere herein. A preferred process for obtainingrecycled hydroxy-phenoxyether polymers comprises providing a papercomprising a hydroxy-phenoxyether polymer, preferably a paper comprisedof an amount of the hydroxy-phenoxyether polymer in the range of fromabout 1% to about 10%, by weight based on total paper weight; contactingthe paper with an aqueous solution comprising about 1-50% acid byweight, preferably 10 to 20% acid by weight, preferably acetic acid orphosphoric acid, to at least partially dissolve the hydroxy-phenoxyetherpolymer to form an acidic hydroxy-phenoxyether polymer solution;separating the acidic hydroxy-phenoxyether polymer solution from anysolids present (e.g., wet cellulosic material); adding a base,preferably a hydroxide of an alkali metal or alkaline earth metal, morepreferably an aqueous solution of NaOH or KOH, to the acidichydroxy-phenoxyether polymer solution to form a hydroxy-phenoxyetherpolymer precipitate; and separating the hydroxy-phenoxyether polymerprecipitate, preferably by settling, decantation, pressing, filtration,or centrifugation. The separated polymer thus recovered is a recycledhydroxy-phenoxyether polymer that may be used in any of the processes ormaterials described herein that call for the use of ahydroxy-phenoxyether polymer.

[0111] In preferred embodiments where the hydroxy-phenoxyether polymeris a thermoplastic, the paper may be recycled directly by heating thepaper to soften or melt the polymer, then molding or otherwiseprocessing the paper into the desired shape to form a product comprisedof recycled paper, in whole or part. Additional polymer, cellulosicmaterial, and/or other additives may be added or removed duringrecycling and/or processing.

Recycling Methods

[0112] In accordance with one preferred embodiment, thehydroxy-phenoxyether polymer used in methods and materials disclosedherein comprises at least some recycled hydroxy-phenoxyether polymer.When, in the discussion below, it states that the fiber or polymer maybe “used”, such uses include, but are not limited to, those discussed inthe present application. One method for obtaining recycledhydroxy-phenoxyether polymer is that in FIG. 9, a flow chart showing apreferred process for obtaining recycled hydroxy-phenoxyether polymerand fiber from articles 910 made with various fibers andhydroxy-phenoxyether polymers. The method noted below may also be usedto recycle other materials which comprise cellulose or other fibers andhydroxy-phenoxyether polymer whether or not such materials may beappropriately designated as “paper.” Other processes and additionaldetails not necessary to repeat here are disclosed in Assignee'scopending application entitled RECYCLING OF ARTICLES COMPRISINGHYDROXY-PHENOXYETHER POLYMERS, application Ser. No. ______ [AttorneyDocket No. APTLTD.021A], filed on the same date as the presentapplication, the entirety of which is hereby incorporated by reference.

[0113] As noted in FIG. 9, the first portions of the method relate topreparation of the articles to be recycled. The first step relates tobreaking the articles down into smaller pieces or “flakes” 912. Becausesome of the articles containing materials to be recycled are relativelylarge, the articles are preferably granulated, chopped, shredded,comminuted, grated, or otherwise made into smaller pieces. The size ofsuch pieces is not important.

[0114] The second part of the process is cleaning 914. The recycledarticles often contain dirt, food particles, grease, labels, adhesive,or other items or debris attached to them which should be removed bycleaning. Cleaning may be accomplished by steam treatment in anaspirator, caustic wash, washing with water either with or withoutcleaning solution, or treatment by solvents or cleaning solutions not inthe presence of water. Preferred cleaning solutions are those which donot dissolve the hydroxy-phenoxyether polymers, e.g. those which areneutral or basic in character or not good solvents for the plastic.Following exposure to the cleaning agents, the materials are optionallyrinsed and/or dried before proceeding with the process.

[0115] Following preparation, the flakes are combined with an aqueoussolution containing about 1-50%, more preferably about 5-20% acetic acidby weight 916. The pH of the solution is preferably below pH 4, morepreferably about pH 3.0-3.5 or less. The flakes are combined with theacid solution for a time period sufficient to result in dissolution ofthe hydroxy-phenoxyether polymer, preferably for about 0.5 to 5 hours atabout 25-95° C. with stirring or agitation.

[0116] Following dissolution of the hydroxy-phenoxyether polymer, thehydroxy-phenoxyether polymer solution 922 is separated from the othermaterials in the mixture, primarily fiber 936. The separation 918 ispreferably done by filtration, but may be done by any method capable ofseparating solids and liquids such as decantation, centrifugation orsettling. The solutions made from recycled materials may be used withoutfurther recycling processing as discussed below, either before or afterseparation of the solid (fiber) portion. Uses for such solutions,include, but are not limited to, the methods and processes disclosed inthe present application.

[0117] The acidic hydroxy-phenoxyether polymer solution may undergoadditional treatment to partially or fully precipitate thehydroxy-phenoxyether polymer from the solution to give a dispersion orsolid. Precipitation 924, whether partial or complete, is done byaddition of one or more basic (alkaline) materials. Preferably, thebasic compound is a strong base such as sodium hydroxide or potassiumhydroxide in the form of a solution. As the base is added, the pH of thesolution will begin to rise. As the pH of the solution approaches pH 4,precipitate may begin to form. As the pH rises above pH 4, the amount ofprecipitate increases, with more precipitate forming at pH 5 and pH 6,until at about pH 7 at which point precipitation is substantiallycomplete.

[0118] The precipitated solutions or dispersions made from recycledmaterials may be used without further recycling processing as discussedbelow. Furthermore, the dispersion formation may be done in the presenceof the fiber (without filtering), following addition of new fibermaterial, or some combination of the two. The dispersions formed fromrecycled materials may be used in the same manner as those formed fromvirgin materials including, but not limited to, the methods andprocesses disclosed in the present application.

[0119] Following precipitation, the hydroxy-phenoxyether polymer isseparated 926 from the liquid component or mother liquor from which theprecipitate formed. The solids may be separated from the liquid by anymethod capable of separating solids and liquids, preferably filtration,pressing, decantation, centrifugation or settling. Thehydroxy-phenoxyether polymer precipitate is preferably rinsed 928 toremove any salts or other materials which may deposit on the precipitatefrom the liquid portions. Preferred rinsing media include water,preferably distilled and/or deionized water, and solvents in which thehydroxy-phenoxyether polymer is insoluble or only marginally soluble,with water being preferred. The rinse water may be heated to aid thedissolution of residues on the precipitate. The precipitate is thendried 928. Drying may be accomplished by air drying, vacuum drying withor without added heat, oven drying, IR lamp drying, desiccants, or othermethods which aid in the evaporation or elimination of water.

[0120] The precipitate may be used following drying or it may beprocessed 930 before use. Further processing of the precipitate prior touse includes, without limitation, pulverization to form a powder andextrusion to form sheets or pellets. Such processing may include theaddition of one or more additives. Suitable additives include, withoutlimitation, mold release agents, dyes, and lubricants. The additives maybe dry mixed with the hydroxy-phenoxyether polymer or added to a melt ofthe hydroxy-phenoxyether polymer.

[0121] Following separation from the acidic hydroxy-phenoxyether polymersolution, the fiber is preferably rinsed 938 with water. The rinse wateris preferably deionized and/or distilled, and either neutral or slightlyacidic so as to deter precipitation of any hydroxy-phenoxyether polymeronto the fiber during rinsing. In accordance with one preferredembodiment, the fiber is first rinsed with an acidic solution having apH below about pH 4, followed by a second rinse with water having a pHat or near neutral.

[0122] The fiber may then be treated by drying or further processing940. Drying of the fiber is done by a method such as air drying, vacuumdrying with or without added heat, oven drying, IR lamp drying,desiccants, or another method which aids in the evaporation orelimination of water. Further processing may be done to influenceproperties of the fiber which may enhance its ability to bind withhydroxy-phenoxyether polymer. Such methods are discussed elsewhereherein, and may be done either before or after drying.

[0123] Paper and other articles treated with lower levels ofhydroxy-phenoxyether polymer for sizing and lower levels of dry or wetstrength could be treated as part of a conventional paper mill recyclingsystem, enabling the cellulose or other such fibers to be recovered andreused without recycling the polymer. If, however, the article or paperhas higher levels of hydroxy-phenoxyether polymer or if recycling of thehydroxy-phenoxyether polymer is desired, a preferred method for suchrecycling is shown in FIG. 10. Referring to FIG. 10, there is analternate method of recycling articles made from fiber andhydroxy-phenoxyether polymer, described in terms of a preferredembodiment using paper made from cellulose.

[0124] Paper for recycling is usually baled and brought to the mill. Thebales are dropped into the pulper 942, a large vat containing water andfitted with a high-shear agitator. The combination of wetting andmechanical action breaks the hydrogen bonds amongst the cellulose fibersto make a pulp slurry. The water in the pulper is acidified 916, asdiscussed above, to dissolve the hydroxy-phenoxyether polymer. Balingwires and other gross contaminants are removed from the pulper by a‘junker’ 944. The pulp and hydroxy-phenoxyether polymer solution isdischarged from the pulper and then cleaned 946 and screened 948 tofurther remove contaminants. The good fiber together with thehydroxy-phenoxyether polymer solution, ‘accepts’ 950, may be processedto make paper 952 or other hydroxy-phenoxyether polymer/fiber materialssuch as are disclosed elsewhere herein, or they may undergo a separationprocess 918. Preferably, separation of the cellulose fibers andhydroxy-phenoxyether polymer solution, and any further processing of thefibers and/or hydroxy-phenoxyether polymer solution proceeds asdiscussed above.

[0125] Materials which are not “accepts” pass into the deflaker 954 andthen through a vibrating screen 956. Any usable pulp material is thenredeposited in the pulper 942 with the remaining undesirable materialsbeing discarded as “rejects” 958.

[0126] Although the foregoing invention has been described in terms ofcertain preferred embodiments, other embodiments will become apparent tothose of ordinary skill in the art in view of the disclosure herein.Accordingly, the present invention is not intended to be limited by therecitation of preferred embodiments, but is intended to be definedsolely by reference to the appended claims.

EXAMPLES Examples 1-5

[0127] Dry tensile, wet tensile and Cobb sizing were determined on aseries of paper sheets prepared from unrefined bleached softwood krafthaving a consistency of 0.75% using a laboratory handsheet former. A 10%solution of a “BLOX®” hydroxy-phenoxyether polymer (BLOX 0005®, DowChemical Co., Midland Mich.) in 8% acetic acid was prepared at 90° C.and while still hot, was diluted with 20% distilled water, giving afinal polymer concentration of 8%. This solution was intermixed with thepulp slurry so that the amount of polymer was 5% by weight, based onweight of cellulosic material, in the resulting handsheets (Examples 2,3 and 4). The basis weight of the handsheets was 315 g/m². Example 1Cwas a comparable paper that was run in the same way as Example 2 exceptwithout hydroxy-phenoxyether polymer. Examples 3 and 4 were run in thesame way as Example 2 except that the polymer was precipitated in thepresence of the pulp slurry by the addition of NaOH or KOH,respectively. Example 5C was run in the same way as Example 2 exceptthat a commercially available wet-strength resin (KYMENE 557, Hercules)was used instead of a hydroxy-phenoxyether polymer. The results in Table1 show that 5% hydroxy-phenoxyether polymer was effective tosubstantially increase the dry tensile strength, wet tensile strengthand sizing of paper into which it was incorporated. As compared toKYMENE 557, wet tensile strength and sizing were substantially improved.TABLE 1 Dry Tensile Wet Tensile Cobb No. Additive Strength (Nm) Strength(Nm) (g/m²) 1C None 1.1 0 854 2 5% BLOX ® 1.7 0.76 13 3 5% BLOX ® + NaOH2.3 0.38 95 4 5% BLOX ® + KOH 2.1 0.78 24 5C 5% KYMENE 557 5.9 0.43 2804

Examples 6-9

[0128] Examples 6-9 were run in the same way as Examples 1-4, exceptthat the basis weight of the paper sheets was 345 g/m² and the amount ofBLOX® was 15% by weight, based on total weight of cellulosic material.The results in Table 2 show that 15% hydroxy-phenoxyether polymer waseffective to substantially increase the dry tensile strength, wettensile strength and sizing of paper into which it was incorporated.TABLE 2 Dry Tensile Wet Tensile Cobb No. Additive Strength (Nm) Strength(Nm) (g/m²) 6C None 1.0 0 919 7 15% BLOX ® 1.6 0.64 45 8 15% BLOX ® +4.6 1.6 25 NaOH 9 15% BLOX ® + KOH 4.7 1.9 24

Examples 10-13

[0129] Examples 10-13 were run in the same way as Examples 1-4, exceptthat the basis weight of the paper sheets was 375 g/m² and the amount ofBLOX® was 25% by weight, based on total weight of cellulosic material.The results in Table 3 show that 25% hydroxy-phenoxyether polymer waseffective to substantially increase the dry tensile strength, wettensile strength and sizing of paper into which it was incorporated.TABLE 3 Dry Tensile Wet Tensile Cobb No. Additive Strength (Nm) Strength(Nm) (g/m²) 10C None 0.9 0 898 11 25% BLOX ® 1.8 1.0 55 12 25% BLOX ® +5.9 2.4 26 NaOH 13 25% BLOX ® + KOH 6.3 2.6 19

Examples 14-16

[0130] Examples 14-16 were run in the same way as Examples 1-4, exceptthat a refined bleached softwood kraft having a consistency of 1.5% wasused instead of the unrefined bleached softwood kraft and no NaOHneutralizations were performed. The results in Table 4 show that 5%hydroxy-phenoxyether polymer was effective to substantially increase thedry tensile strength, wet tensile strength and sizing of paper intowhich it was incorporated. TABLE 4 Dry Tensile Wet Tensile Cobb No.Additive Strength (Nm) Strength (Nm) (g/m²) 14C None 6.3 0.2 646 15 5%BLOX ® 7.6 2.0 371 16 5% BLOX ® + KOH 7.5 3.8 27

Examples 17-19

[0131] Examples 17-19 were run in the same way as Examples 6-9, exceptthat a refined bleached softwood kraft having a consistency of 1.5% wasused instead of an unrefined bleached softwood kraft and no NaOHneutralizations were performed. The results in Table 5 show that 15%hydroxy-phenoxyether polymer was effective to substantially increase thedry tensile strength, wet tensile strength and sizing of paper intowhich it was incorporated. TABLE 5 Dry Tensile Wet Tensile Cobb No.Additive Strength (Nm) Strength (Nm) (g/m²) 17C None 7.8 0.23 782 18 15%BLOX ® 8.56 3.3 295 19 15% BLOX ® + KOH 11.6 5.2 28

Examples 20-22

[0132] Examples 17-19 were run in the same way as Examples 10-13, exceptthat a refined bleached softwood kraft having a consistency of 1.5% wasused instead of an unrefined bleached softwood kraft and no NaOHneutralizations were performed. The results in Table 6 show that 25%hydroxy-phenoxyether polymer was effective to substantially increase thewet tensile strength and sizing of paper into which it was incorporated.TABLE 6 Dry Tensile Wet Tensile Cobb No. Additive Strength (Nm) Strength(Nm) (g/m²) 20C None 9.1 0.35 897 21 25% BLOX ® 8.36 3.9 26 22 25%BLOX ® + KOH 10.8 4.62 39

Examples 23-25

[0133] Examples 23-25 were run in the same way as Examples 1-4, exceptthat a pulp slurry of repulped egg boxes having a consistency of 0.75%was used instead of the unrefined bleached softwood kraft and no NaOHneutralizations were performed. The results in Table 7 show that 5%hydroxy-phenoxyether polymer was effective to substantially increase thedry tensile strength, wet tensile strength and sizing of paper intowhich it was incorporated. TABLE 7 Dry Tensile Wet Tensile Cobb No.Additive Strength (Nm) Strength (Nm) (g/m²) 23C None 4.4 1.9 93 24 5%BLOX ® 4.5 3.4 14 25 5% BLOX ® + KOH 6.8 4.2 24

Examples 26-28

[0134] Examples 26-28 were run in the same way as Examples 6-9, exceptthat a pulp slurry of repulped egg boxes having a consistency of 0.75%was used instead of the unrefined bleached softwood kraft and no NaOHneutralizations were performed. The results in Table 8 show that 15%hydroxy-phenoxyether polymer was effective to substantially increase thedry tensile strength, wet tensile strength and sizing of paper intowhich it was incorporated. TABLE 8 Dry Tensile Wet Tensile Cobb No.Additive Strength (Nm) Strength (Nm) (g/m²) 26C None 5.2 1.9 157 27 15%BLOX ® 6.0 5.2 26 28 15% BLOX ® + KOH 6.4 5.1 21

Examples 29-31

[0135] Examples 29-31 were run in the same way as Examples 10-13, exceptthat a pulp slurry of repulped egg boxes having a consistency of 0.75%was used instead of the unrefined bleached softwood kraft and no NaOHneutralizations were performed. The results in Table 9 show that 25%hydroxy-phenoxyether polymer was effective to substantially increase thedry tensile strength, wet tensile strength and sizing of paper intowhich it was incorporated. TABLE 9 Dry Tensile Wet Tensile Cobb No.Additive Strength (Nm) Strength (Nm) (g/m²) 29C None 4.9 3.3 46 307 25%BLOX ® 5.7 4.8 30 31 25% BLOX ® + KOH 6.7 4.5 21

Examples 32-41

[0136] Paper sheets were prepared by the general procedure of Examples1-4, except that the amount of polymer was 0% (control), 5%, 10%, 20%and 40% and all of the polymers were neutralized with KOH. The resultingsheets were then pulp molded to produce samples 1.5 mm and 2.5 mm inthickness and the compressive strengths of these samples were measuredas shown In FIG. 1. FIG. 2 shows the results of cyclic compressiontesting. These results show that hydroxy-phenoxyether polymer waseffective to substantially increase the compressive strength of paperinto which it was incorporated.

Example 42

[0137] Paperboard samples from 26 lbs. to 69 lbs. stock were coated witha dispersion of hydroxy-phenoxyether polymer. The polymer was found toprovide significant increase in water repellency. At 15 grams/m² of coatweight, the paper passed the 3M oil resistance test (3M Kit Test, TAPPIUseful Method 557) up to the # 12 test solution (45% toluene and 55%heptane). The test results showed that the coated paper provided variouslevels of protection with the greatest protection provided by a coatingwith a thickness estimated to be about 0.5 - 1.0 mil thick. Impregnatedpaper coated with the polymer film (estimated coating thickness of about0.5 mil) passed the # 12 soak test.

Example 43C-48

[0138] Handsheets were prepared as described in Example 2 above exceptthat the basis weight of the sheets was 360 g/m² (300 grams cellulosicmaterial, 60 grams polymer). Then sheets were then repulped in eitherwater or an 8% acetic acid solution to produce two batches of slurry, anwater batch and an acetic acid batch.

[0139] The recyclability of the cellulosic material and the polymer wasthen assessed for each of the two batches in two different ways. In thefirst way, handsheets were made in the manner described above from boththe water batch (“Re-made w/water”) and the acetic acid batch (Re-madew/acetic acid”), using KOH. In the second way, the water and acetic acidsolutions were separated from the cellulosic material in each of thewater and acetic acid batches, respectively, and each combined withfresh cellulosic material and KOH to make a new water slurry and a newacetic acid slurry, respectively. Handsets were then prepared asdescribed above from the new water slurry (“New w/water”) and from thenew acetic acid slurry (“New w/acetic acid), using KOH.

[0140] The burst strength and Cobb sizing of each of the four groups ofrecycled sheets was measured, along with the burst strengths and Cobbsizing of the initial, unrecycled sheets (“Initial”) and control sheetsmade without polymer (“Control”). The results are below in Table 10under the heading “1^(st) Recycle.” Each of the sheets were then d againas described above to form new sheets. The strengths and sizing of thesere shown under the heading “2^(nd) Recycle” in Table 10. TABLE 10 BurstStrength Cobb Sizing (±10 kPa) (±50 gsm) 1^(st) 2^(nd) 1^(st) 2^(nd) Ex.Paper Recycle Recycle Recycle Recycle 43C Control 125 125 1800 1800 44Initial 500 500 100 100 45 Re-made 250 190 1750 1700 w/water 46 Re-made210 180 200 450 w/acetic acid 47 New w/water 200 180 1550 1750 48 New250 220 80 120 w/acetic acid

What is claimed is:
 1. Paper comprised of an amount of ahydroxy-phenoxyether polymer that is effective to provide said paperwith an increase in sizing or strength.
 2. Paper as claimed in claim 1,wherein said hydroxy-phenoxyether polymer is a polyetheramine.
 3. Paperas claimed in claim 1, wherein said amount of a hydroxy-phenoxyetherpolymer is in the range of about 0.5% to about 20%, by weight based ontotal paper weight.
 4. Paper as claimed in claim 1, wherein saidincrease in sizing is manifested as a decrease in Cobb sizing of about5% or more, as compared to a comparable paper that does not contain ahydroxy-phenoxyether polymer.
 5. Paper as claimed in claim 1, whereinsaid increase in sizing is manifested as an increase in resistance tooil or grease, as compared to a comparable paper.
 6. Paper as claimed inclaim 1, wherein said increase in sizing is effective to provide saidpaper with a Cobb sizing value of about 50 g/m² or less.
 7. Paper asclaimed in claim 1, wherein said increase in strength is an increase inwet tensile strength, dry tensile strength, wet flexural strength, ordry flexural strength of about 5% or more, as compared to a comparablepaper that does not contain a hydroxy-phenoxyether polymer.
 8. Paper asclaimed in claim 1, wherein said paper is corrugated paper and whereinsaid increase in strength is an increase in wet flexural strength, 9.Paper as claimed in claim 1, wherein said paper is less permeable tooxygen, carbon dioxide, nitrogen, or water vapor as compared to acomparable paper that does not contain a hydroxy-phenoxyether polymer.10. A manufactured article comprised of the paper of claim
 1. 11. Amanufactured article as claimed in claim 10 in the form of a container.12. A manufactured article as claimed in claim 10 in the form of ahoneycomb structure.
 13. A process for making paper, comprisingproviding a pulp slurry or paper web, providing a solution or dispersioncomprising a hydroxy-phenoxyether polymer, intermixing said solution ordispersion with said pulp slurry or paper web to form an admixture, andforming paper from said admixture, wherein said hydroxy-phenoxyetherpolymer is used in an amount that is effective to provide said paperwith an increase in sizing or strength.
 14. A process as claimed inclaim 13, which further comprises adjusting the pH of said admixture toprecipitate a least a portion of said hydroxy-phenoxyether polymer. 15.A process as claimed in claim 13, which further comprises adjusting thepH of said admixture to be in the range of about 4 to about
 7. 16. Aprocess as claimed in claim 13, wherein said intermixing is carried outby spraying said solution or dispersion onto said paper web.
 17. Aprocess as claimed in claim 13, wherein said dispersion has a numberaverage particle size of about 100 microns or less.
 18. A process asclaimed in claim 13, wherein said hydroxy-phenoxyether polymer comprisesa recycled hydroxy-phenoxyether polymer.
 19. A process as claimed inclaim 18, wherein said increase in strength is an increase in wettensile strength, dry tensile strength, wet flexural strength, or dryflexural strength of about 5% or more, as compared to a comparable paperthat does not contain a hydroxy-phenoxyether polymer.
 20. A process forcoating paper, comprising providing a paper, providing a solution ordispersion comprising a hydroxy-phenoxyether polymer, applying saidsolution or dispersion to at least a portion of said paper to form a wetpaper, and drying said wet paper to form a coated paper.
 21. A processas claimed in claim 20, which further comprises heating said wet paper.22. A process as claimed in claim 20, wherein said coated paper has aCobb sizing value of about 100 or less.
 23. A process as claimed inclaim 20, wherein said coated paper is comprised of from about 1% toabout 30%, by weight based on total coated paper weight, of saidhydroxy-phenoxyether polymer.
 24. A process as claimed in claim 20,which further comprises forming a wet laminate by bringing said wetpaper or said coated paper into contact with a solid material, a secondsolution or dispersion comprised of a hydroxy-phenoxyether polymer, or amixture thereof, and drying said wet laminate to form a laminate.
 25. Alaminate comprised of hydroxy-phenoxyether polymer, at least one layercomprised of paper, and at least one layer comprised of a second paperor a solid non-paper material.
 26. A laminate as claimed in claim 25,wherein said laminate is made by the process of claim
 19. 27. A laminateas claimed in claim 25, wherein said hydroxy-phenoxyether polymer is apoly(hydroxyamino ether) or a poly(hydroxy ester ether).
 28. A laminateas claimed in claim 25, wherein said non-paper material is selected fromthe group consisting of metal, textile fabric, foam, thermoplasticpolymer, thermoset polymer, and filled polymer.
 29. A laminate asclaimed in claim 25 that displays synergistic strength.
 30. A laminateas claimed in claim 25 which is further comprised of a fibrous material.31. A laminate as claimed in claim 30, wherein said fibrous material isselected from the group consisting of plant fibers made from wood pulp,cotton fibers, hemp, bagasse, abaca, flax, southern pine, southernhardwood fibers, cellulose, wheat, starch, modified starch, chitin,chitosan, keratin, cellulose acetate, cellulose materials derived fromagricultural products, gluten, nut shell flour, wood flour, corn cobflour, guar gum, and mixtures thereof.
 32. A laminate as claimed inclaim 25, wherein said laminate is less permeable to oxygen, carbondioxide, nitrogen, or water vapor as compared to a comparable laminatethat does not contain a hydroxy-phenoxyether polymer.
 33. A laminate asclaimed in claim 25, wherein said laminate is comprised of an amount ofa hydroxy-phenoxyether polymer that is effective to provide the laminatewith an increase in sizing.
 34. A laminate as claimed in claim 33,wherein said increase in sizing is manifested as an increase inresistance to water, oil or grease, as compared to a comparablelaminate.
 35. A method of obtaining recycled hydroxy-phenoxyetherpolymers from paper comprising hydroxy-phenoxyether polymers,comprising: providing a paper comprising a hydroxy-phenoxyether polymer;contacting said paper with an aqueous solution comprising 1-50% acid byweight to at least partially dissolve said hydroxy-phenoxyether polymerto form an acidic hydroxy-phenoxyether polymer solution; separating saidacidic hydroxy-phenoxyether polymer solution from any solids present;adding a base to said acidic hydroxy-phenoxyether polymer solution toform a hydroxy-phenoxyether polymer precipitate; and separating saidhydroxy-phenoxyether polymer precipitate.
 36. The method of claim 35,wherein said acid is acetic acid or phosphoric acid.
 37. The method ofclaim 35, wherein said base is a hydroxide of an alkali metal oralkaline earth metal.
 38. The method of claim 35, wherein the aqueoussolution comprises 10-20% acid by weight.
 39. The method of claim 35,wherein said paper is comprised of an amount of saidhydroxy-phenoxyether polymer in the range of from about 1% to about 10%,by weight based on total paper weight.